CHANGE IN TAENIASIS TESTING · CHANGE IN TAENIASIS TESTING The Public Health Impact Roshan...
Transcript of CHANGE IN TAENIASIS TESTING · CHANGE IN TAENIASIS TESTING The Public Health Impact Roshan...
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CHANGE IN TAENIASIS TESTING
The Public Health Impact
Roshan Reporter, MD MPHAcute Communicable Disease Control
Los Angeles CountyDepartment of Public Health
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CASE REPORT
• 16 month-old traveled to Taiwan– generalized seizure upon return
• Evaluation revealed– multiple bilateral ring-enhancing lesions with
surrounding edema
• Case reported to Public Health
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CASE REPORT - 2
• PHN conducted home visit– Obtained history of risk factors– Requested stool specimens of household– Baby, sib & parents negative for pathogens
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CASE REPORT - 3
• Live-in Baby-sitter– native of Guatemala– positive for Taenia solium– treatment rendered her non-infectious
• Supported neurocysticercosis diagnosis
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CYSTICERCOSISSIGNS AND SYMPTOMS
• Muscles-may feel lumps• Eyes-blurry vision, swelling, detached retina• Brain-headaches, seizures
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Calcified cysticerci
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Cysticercosis in the eye
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Neurocysticercosis
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LIFE CYCLE
Los Angeles County Department of Health Services
When eggs from person
with T. solium are ingested by another
person, cysticercosis may occur.
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T. Solium Egg
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SCREENING FOR TAENIA
• Sorvillo, 1988-1990: N=138– 63 index cases (46%) tested– only one positive (1.6%)
– 347 contacts to 72 index cases tested– 6 contacts of 5 cases positive for Taenia– Carriers more likely among contacts of US-born
cases (22%) than immigrants (4.8%)
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SCREENING FOR TAENIA - 2
Dassey case study: 1994-1998*– only 42 / 120 cases screened (35%)
• 10 / 21 USA natives (48%)• 32 / 99 immigrants (32%)
– no positives found
– unknown number of contacts screened• one positive contact
*Unpublished study
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CYSTICERCOSIS REPORTING
• Cysticercosis remains a persistent threat in Los Angeles County (and presumably other border states).
• Cases are predominantly immigrant Hispanics under 40 years of age.
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CYTICERCOSIS REPORTING- 2
• Reporting to public health by physicians and hospitals must improve.
• Once reported, PH can screen index cases and their close contacts for tapeworms.
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CYSTICERCOSIS REPORTING-3
• Some tapeworm carriers work in critical settings.
– food handling– child care– medical care
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Adult Tapeworm
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Taenia solium scolex
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PUBLIC HEALTH MESSAGE
• Identification of tapeworm carriers – allows for them to be treated, thus– eliminating further risk of cysticercosis
transmission to themselves and others.
• Public Health staff can identify and screen close contacts at no charge and refer for treatment.
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TESTING FOR TAENIASIS-WHY CHANGE?
• To improve diagnosis of taeniasis using a test with improved sensitivity.
• To identify possible sources of infection (tapeworm carriers) among household contacts and other close personal contacts of cysticercosis cases.
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PHN ROLE
• PHN interviews using standardized case investigation form for cysticercosis
• Information is also collected on household members and other close personal contacts.
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CURRENT SCREENING TEST
• Contacts are offered testing for taeniasis by O&P– Lower sensitivity– Three stool specimens required– Low compliance by contacts– Cannot speciate Taenia by O&P
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NEW SCREENING TEST
• Serologic (blood) test• More sensitive and specific than stool O&P
– 95% sensitivity– 100% specificity –no false positives
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SEROLOGIC TEST RESULTS
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NEW SCREENING TEST-2
• PHN to collect fingerstick specimen– Can be done in the field– Only one visit needed to collect specimen– If refuse blood test, offer O&P x 3 stool testing
• Contacts diagnosed with taeniasis will be referred for treatment
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PUBLIC HEALTH MESSAGE
• Identification of tapeworm carriers – allows for them to be treated, thus– eliminating further risk of cysticercosis
transmission to themselves and others.
• Public Health staff can identify and screen close contacts at no charge and offer or refer for treatment.
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Questions?
• Slides from this CEU program will be posted after the In-service.
• Educational slide show from the UN:• www.fao.org/ag/againfo/programmes/docume
nts/.../TaeniaSoliumFAO1.swf
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Taenia solium scolex